Brief History of Head Lice

Beginning somewhere around 13 million years ago, specific species began to evolve to affect only humans. Pediculus lice are among oldest human parasites and have a long history of association with humans. They accompanied early Homo groups as they migrated out of Africa. As such they represent good markers for tracking human history.

About 42,000 to 72,000 years ago, human lice separated into head and body lice.

Indeed, phylogenetic analyses of Pediculus lice have confirmed some events in the human evolution, such as the estimation date of H. sapiens when began wearing clothing, by estimating the age of the body louse (approximately 170,000 years ago), which would first emerged only after the start of clothing use by humans, since the female body louse lays eggs exclusively on the host’s clothing. Moreover, lice population show the signs of a recent demographic expansion that occurred roughly 100,000 years ago, coinciding with the spread of H. sapiens out of Africa. Thus, allowing the use of lice to resolve some of the issues related to our understanding of human migration, such as the timing and trajectories of New Word colonization. In recent years, several fossil records of lice and nits from different archaeological sites have been expanded. The earliest ancient specimen of head lice nits, dating back 10,000 years, was found in Brazil, South America.